Lamp assembly for edge lighted panel

ABSTRACT

A lamp with a bulb slidable within a housing. A spring member within the housing urging the bulb outward for engagement with a fixed contact when the lamp is placed in a socket, such as a metal ring mounted on a printed circuit board. A retainer on the housing for keeping the bulb in the housing and also providing a bayonet type base for mounting the lamp in a socket. A lamp with a spring loaded movable bulb for insertion and removal from the front surface of an edge lighted instrument panel.

Ullit'ed States Patent 1 1 Dupree Sept. 4, 1973 [54] LAMP ASSEMBLY FOREDGE LIGHTED 2,847,654 8/ 1958 Peak et a1. 339/130 R PANEL 2,884,6094/1959 Fraser et al.... 339/17 D 75 l J N D S h El 3,100,085, 8/1963Dover 339/127 R X t s t t l 1 6 FOREIGN PATENTS OR APPLICATIONS1,123,304 8 1968 G t B 'ta' 33917 D [73] Assignee: Dupree, Inc., ElMonte, Calif. I ma n m I [22] Filed: Jan. 10, 1972 PrimaryExaminer-Marvin A. Champion Assistant Examiner-Terrell P. Lewis [21]Appl' 216852 I Attorney-Harris, Kern, Wallen & Tinsley Related U.S.Application Data [62] Division of Ser. No. 55,905, .luly 17, 1970. [57]ABSTRACT v A lamp with a bulb slidable within a housing. A spring [52]U.S. Cl. 339/17 D, 240/816, 339/145 R em r wi hinth hou ing urging thebulb outward for [51] Int. Cl. H01r 33/46, H051: 1/18 g g n i h a fixecon ct when the lamp is [58] Field of Search 339/17, 18, 88, 89, placedin a socket, Such as a metal g m nt d n :1 339/119, 125, 126, 127, 130,131, 132, 144, printed circuit board. A retainer on the housing for 145,147, 176, 180, 188; 240/8.l6 keepingthe bulb in the housing and alsoproviding a I bayonet type base for mounting the lamp in a socket. [56]Referenges Cit d A lamp with a spring loaded movable bulb for insertionUNITED STATES PATENTS and removal from thefront surface of an edgelighted 3,005,907 10/1961 Dupree 240/8.l6 msmmem panel 3,176,255 3/19653 Claims, 8 Drawing Figures Jensen 339/130 R X 34 A p i V 15 3-1,; .M a;a? )5- LAMP ASSEMBLY FOR EDGE LIGHTED PANEL This is a division ofapplication Ser. No. 055,905, filed July 17, I970.

This invention relates to lamps having an electric light bulb andintended to be removably mounted in a socket. A lamp and socketcombination desirably should have a resilient or moving member formaintaining pressure at the electrical contacts between the twocomponents. Customarily, the lamp structure is a fixed or rigidcomponent and the resilient or moving member is incorporated into thesocket. In general, most maintenance problems arise in conjunction withmoving parts rather than with fixed parts, and, except for bulbburn-out, most maintenance work on lamp and socket combinations requireswork on the socket rather than the lamp. This problem has now beensolved to some degree by providing a socket with no moving parts and alamp with the moving parts incorporated therein, as shown in my U.S.Pat. No. 3,506,943, entitled Lamp Socket Assembly, and in my copendingapplication for United States patent, Ser. No. 650,518, filed June 30,1967, now allowed, entitled Lamp With Spn'ng Biased Contact.

The present invention is directed to a further improvement in lamps andis particularly suitable for use with edge lighted panels. Edge lightedpanels are widely used in instrument panels and the like, such as inaircraft cockpits. A typical edge lighted panel will include a sheet ofclear or translucent plastic with an opaque coating on the frontsurface. A printed circuit board may be positioned at the back surfaceof the plastic sheet to provide appropriate electrical circuitry.Various switches, lamps and other devices may be mounted on a supportplate with the printed circuit board and the plastic sheet placedthereover, and with the switches, etc., projecting through the frontsurface of the sheet. Legends will be provided on the panel by cuttingthrough the opaque coating. Visibility of the legends is enhanced by'incorporating one or more light sources at edges of the plastic sheetand/or in openings in the plastic sheet at various locations throughoutthe sheet. In a typical installation, a socket is mountd on the circuitboard and is positioned within an opening in the plastic sheet. A lampis installed in the socket in the opening in the plastic sheet andprovides the edge illumination for the sheet. The present invention isdirected to a new and improved lamp and socket.

The objects, advantages, features and results of the invention will morefully appear in the course of the following description. The drawingsmerely show and the description merely describes a preferred embodimentwhich is given by way of illustration or example.

In the drawings:

FIG. 1 is an isometric view of a lamp incorporating a preferredembodiment of the present invention;

FIG. 2 is a longitudinal sectional view of the lamp of FIG. 1;

FIG. 3 is a longitudinal sectional view of a portion of an edge lightedpanel showing a preferred embodiment of the socket for the lamp of FIG.1;

FIG. 4 is a view showing the lamp of FIG. 2 mounted in the socket ofFIG. 3;

FIG. 5 is an isometric view of the socket of FIG. 3;

FIG. 6 is a sectional view taken along the line 6-6 of FIG. 5;

FIG. 7 is a plan view of the circuit board of the edge lighted panel ofFIG. 3; and

FIG. 8 is an end view of the bulb of the lamp of FIGS. 1 and 2 showingthe electrical lead configuration.

FIGS. 1 and 2 illustrate a lamp 10 having a housing including a sleeve11, a cap 12 and a retainer 13. A bulb 14 is positioned within thehousing sleeve 11, with a resilient member such as a spring 15 betweenthe housing cap 12 and bulb l4 urging the bulb outward from the housing.

The bulb has electrical conducting leads 20, 21 joined to a filament 22.A contact disc 23 may be soldered or welded to the outer end of the lead21 providing a center terminal for the lamp, with the space between theglass of the bulb and the contact 23 filled with a nonconductor such asan epoxy cement 24.

The other lead 20 of the bulb may be used to provide a resilient contactwith the retainer 13, with the retainer preferably serving as oneelectrical terminal for the lamp, the disc 23 being the other electricalterminal. The lead 20 may be connected to the retainer 13 by welding orsoldering. In the embodiment illustrated, the lead 20 is formed into agenerally circular configuration (FIG. 8), generally in a planeperpendicular to the vertical axis of the lamp as viewed in FIG. 2, andis connected to the retainer 13 adjacent the outer end of the lead.

The sleeve 11 of the lamp housing preferably is formed of an electricalinsulating material and typically may be a clear or colored ortranslucent plastic. The housing cap 12 also preferably is formed of anelectrical insulating material and typically may be an opaque plastic.With this arrangement, light from the bulb is directed radially but notaxially from the lamp. The cap 12 may have a shoulder 30 positionedwithin the sleeve 11, with the cap and sleeve cemented together. Aplurality of projections 31 may be provided on the cap to enhance thegrip for rotating the lamp during insertion and removal.

A gasket 32 may be positioned about the sleeve 11 and abutting aprojecting portion 33 of the cap. The gasket may be made of a flexiblematerial such as neoprene and preferably includes an outwardly flaringflange 34 directed toward the terminal end of the lamp for pressureengagement with the edge lighted panel to provide a light seal aroundthe lamp, as is best seen in FIG. 4.

In the preferred embodiment illustrated, the retainer 13 is a metal cup38 with a central opening 39 and opposed radially projecting bosses 40.The retainer is affixed to the sleeve after the cap, spring and bulbhave been installed, by bending one or more flanges 41 of the cup 38inwardly into corresponding notches 42 provided in the sleeve 11.

Referring now to FIG. 3, the edge lighted panel depicted thereinincludes a plastic sheet 45 with a printed circuit board 46 carried atthe back side of the plastic sheet 45. A lamp socket 47 is mounted onthe board 46 and projects into an opening 48 in the plastic sheet 45.The opening 48 may be cylindrical, or may be stepped as shown in FIG. 3,or may have other configurations as desired. The panel may be disposedagainst a support plate 49 carrying various switches, etc., (not shown).The circuit board 46 includes electrical conductors 50, 51, 52 which mayhave the configurations shown in FIG. 7.

The socket 47 may. take the form of a metal cup 55 having a centralopening 56 and opposed notches 57. The open upper end 58 of the cup isdesigned to receive the lamp and includes opposed enlarged sections 59for the projecting bosses 40 of the lamp. Opposed recesses 60 areprovided in the wall of the cup 55 for receiving the bosses 40 after thelamp has been inserted and rotated.

The socket 47 is mounted on the board 46, as by soldering the socket tothe conductors 51, 52 (FIG. 3). The socket provides a circuit pathbetween the conduc tors 51, 52, and the notches 57 in the socket provideclearance so that the socket does not make contact with the conductor50. The installation of the lamp in the socket of the edge lighted panelis illustrated in FIG. 4. Before the lamp is inserted, the spring urgesthe bulb 14 outward to the position of FIG. 2, with engagement of thebulb lead with the retainer 13 blocking further movement of the bulb.The lamp is inserted by sliding the housing into the opening of theplastic panel and sliding the retainer 13 into the socket 47, with thebosses 40 passing through the passages provided by the sections 59.After the lamp is in the socket, the lamp is rotated to bring the bosses40 into alignment with the recesses 60. The components of the lamp andsocket are dimensioned so that the contact 23 at the end of the bulbengages the conductor 50 of the board, causing the bulb to slide withinthe lamp housing and compress the spring 15. When the lamp is releasedin the installed position of FIG. 4, the spring urges the lamp housingupward providing a pressure contact between the retainer 13 and thesocket 47, and urges the bulb downward providing a pressurecontactbetween the bulb contact 23 and the conductor 50.

The output or illumination intensity of the bulbs is in a generallyfigure eight pattern. In the preferred embodiment, the filament 22 andthe bosses 40 of each lamp are disposed in the same plane so that theillumination intensity in the panel can be controlled by suitablyorienting the sockets on the circuit board.

The flange 34 of the gasket 32 covers the sleeve 11 of the lamp housingand the opening 48 of the plastic sheet so that light from the lamp doesnot escape to the front face of the panel (upward as viewed in FIG. 4).This arrangement provides the desired edge lighting for the plasticsheet, with the only light visible being through the legends in theopaque coating 65 on the front surfaces of the plastic sheet 45.

The lamp is removed from the socket by pressing inward to additionallycompress the spring 15, and then rotating the lamp to bring the bosses40 into alignment with the sections 59. The spring 15 will then push thelamp outward or it may be pulled out manually. In normal use, the entirelamp is discarded when the bulb burns out, and a new lamp is installed.

Most edge lighted panels have many holes for the lights and othercomponentspositioned therein, leaving very little surface on the circuitboard for the conductors. The resulting circuit paths on the board areusually quite complicated. The socket 47 by interconnecting the twoconductors 51, 52 provides a crossover of the conductor 50, permittingsimpler circuit paths and redundancy in the circuitry.

Although an exemplary embodiment of the invention has been disclosed anddiscussed, it will be understood that other applications of theinvention are possible and that the embodiment disclosed may besubjected .to various changes, modifications and substitutions withoutnecessarily departing from the spirit of the invention.

I claim:

1. In combination:

an insulating board having at least two electrical conductors on oneface thereof; and

a lamp socket consisting of an annular metal member mounted on saidboard at said one face and fixed rigidly in electrical and mechanicalengagement with one of said board conductors, with the other of saidboard conductors positioned centrally of said socket, with all of saidsocket on one side of said board.

2. A combination as defined in claim 1 in which said insulating boardhas first, second and third conductors on one face thereof, with saidfirst conductor disposed between said second and thrid conductors, and

with said socket having spaced depending portions fixed rigidly inelectrical and mechanical engage- 'ment with said second and thirdconductors, respectively, providing an electrical circuit therebetween,and

with said first conductor positioned between said depending portions.

3. A combination as defined in claim 1 including:

a housing;

a bulb slidably carried within said housing;

a resilient member positioned within said housing in engagement withsaid housing and bulb, urging said bulb out of said housing;

said housing including a retainer for engaging said bulb blockingmovement of said bulb out of said housing, with said bulb sliding withinsaid housing toward and away from said retainer;

said housing, bulb and resilient member forming a lamp, with said lamppositioned in said socket with said housing engaged with said socket andwith said bulb engaging the other of said board conductors.

1. In combination: an insulating board having at least two electricalconductors on one face thereof; and a lamp socket consisting of anannular metal member mounted on said board at said one face and fixedrigidly in electrical and mechanical engagement with one of said boardconductors, with the other of said board conductors positioned centrallyof said socket, with all of said socket on one side of said board.
 2. Acombination as defined in claim 1 in which said insulAting board hasfirst, second and third conductors on one face thereof, with said firstconductor disposed between said second and thrid conductors, and withsaid socket having spaced depending portions fixed rigidly in electricaland mechanical engagement with said second and third conductors,respectively, providing an electrical circuit therebetween, and withsaid first conductor positioned between said depending portions.
 3. Acombination as defined in claim 1 including: a housing; a bulb slidablycarried within said housing; a resilient member positioned within saidhousing in engagement with said housing and bulb, urging said bulb outof said housing; said housing including a retainer for engaging saidbulb blocking movement of said bulb out of said housing, with said bulbsliding within said housing toward and away from said retainer; saidhousing, bulb and resilient member forming a lamp, with said lamppositioned in said socket with said housing engaged with said socket andwith said bulb engaging the other of said board conductors.